According to the Guardian, the novel will come out from Viking in spring 2014, with Yuki still in there, along with a lesbian couple who are supporting characters. Brown tells the Guardian that they were never tempted to "straight-wash" the characters because they wanted this book to be about the people that most young-adult books usually leave out. And she said that she'd heard from lots of other authors and editors who reported similar attempts to remove LGBT or minority characters from YA fiction. Said Brown to the Guardian:

We noticed that while there are lots of excellent realistic books about the troubles and difficulties of being a minority, there was very little fun, escapist fiction about teenage wizards or vampires or mutants who aren't white and straight. And of what little there was, most had those characters as sidekicks to the straight white protagonist. So the many teens we knew who preferred fantasy almost never got to read about heroes like themselves," she said. "We didn't do this to fulfil some imaginary quota, but because we wanted to write about teenagers like the real ones we know, [and] making gay characters straight would have gone against the entire reason why we wrote the book in the first place.

And she cited a statistical analysis of American YA novels by Malinda Lo, which found that fewer than 1 percent had any LGBT characters, even in a supporting role. More details at the link. [Guardian]